In data networking, dynamic routing is a way to send data, e.g. data streams from a source/transmitting node to a destination/receiving node by taking into account changes in the network during transmission. If the data stream is sent over different types of networks, e.g. Private Networks, Wide Area Networks (WAN) or Cloud Backbones, firewalls between the different networks can make the transmission more complicated. Further parameters to consider can be e.g. the use of different protocols or that a composition of a multiple of streams is required. The challenge is to deploy processing and forwarding units in the nodes of the data network so that maximum quality to cost can be achieved when sending streams over the network. In the case of live streams, where possible allowed delays are less than about 50 ms, it's even more important that the network can handle a broken line without disturbing the transmission. Live streams are used for example in applications which require voice transmissions such as in conferencing or collaboration contexts.
Current conferencing or collaboration solutions are usually implemented using peer-to-peer or peer-to-server. Most of them solve the case where one transmitter sends to many receivers by using Multipoint Control Units (MCU's). Additional processing power might be added in these MCU's (e.g. transcoding, composition, transrating or resizing) but the data streams are usually routed through pre-defined fixed nodes that have fixed locations in the network. The data stream will normally enter or exit such systems at the server closest to the destination point. And possible optimization of the routes (and the processing) is obtained through pre-defined and fixed rules. These solutions are limited to processing multimedia data. So-called “content providers” (e.g. video-on-demand) often need to route between different types of networks and over large distances, but they have no requirement to work with live streams. On the other hand they can buffer the data streams for “long times”, e.g. several minutes, before starting the transmission. And if later on re-routing is needed, this can be performed within the buffer time interval without the end-user noticing
U.S. Pat. No. 6,981,055B1 describes how to optimize routing in a network of border gateways through multiple internet route providers. The method comprises making routing decisions based on performance measurements associated with a plurality of alternative paths. Re-routing is performed by using the last received routing table.